Mohamed Kezzar, Nabil Talbi, Saeed Dinarvand, Sanatan Das, Mohamed Rafik Sari, Samia Nasr and Ali Akhlaghi Mozaffar
This paper aims to model and analyze Jeffery Hamel’s channel flow with the magnetohydrodynamics second-grade hybrid nanofluid. Considering the importance of studying the velocity…
Abstract
Purpose
This paper aims to model and analyze Jeffery Hamel’s channel flow with the magnetohydrodynamics second-grade hybrid nanofluid. Considering the importance of studying the velocity slip and temperature jump in the boundary conditions of the flow, which leads to results close to reality, this paper intends to analyze the mentioned topic in the convergent and divergent channels that have significant applications.
Design/methodology/approach
The examination is conducted on a EG-H_2 O <30%–70%> base fluid that contains hybrid nanoparticles (i.e. SWCNT-MWCNT). To ensure comprehensive results, this study also considers the effects of thermal radiation, thermal sink/source, rotating convergent-divergent channels and magnetic fields. Initially, the governing equations are formulated in cylindrical coordinates and then simplified to ordinary differential equations through appropriate transformations. These equations are solved using the Explicit Runge–Kutta numerical method, and the results are compared with previous studies for validation.
Findings
After the validation, the effect of the governing parameters on the temperature and velocity of the second-grade hybrid nanofluid has been investigated by means of various and comprehensive contours. In the following, the issue of entropy generation and its related graphical results for this problem is presented. The mentioned contours and graphs accurately display the influence of problem parameters, including velocity slip and temperature jump. Besides, when thermal radiation is introduced (Rd = +0.1 and Rd = +0.2), entropy generation in convergent-divergent channels decreases by 7% and 14%, respectively, compared to conditions without thermal radiation (Rd = 0). Conversely, increasing the thermal sink/source from 0 to 4 leads to an 8% increase in entropy generation at Q = 2 and a 17% increase at Q = 4 in both types of channels. The details of the analysis of contours and the entropy generation results are fully mentioned in the body of the paper.
Originality/value
There are many studies on convergent and divergent channels, but this study comprehensively investigates the effects of velocity slip and temperature jump and certainly, this geometry with the specifications presented in this paper has not been explored before. Among the other distinctive features of this paper compared to previous works, the authors can mention the presentation of velocity and temperature results in the form of contours, which makes the physical analysis of the problem simpler.
Details
Keywords
The purpose of this paper is to present the physical context of the necropolis of Bat, look at its management by the Omani Ministry of Heritage and Culture (MHC), and discusse the…
Abstract
Purpose
The purpose of this paper is to present the physical context of the necropolis of Bat, look at its management by the Omani Ministry of Heritage and Culture (MHC), and discusse the challenges it is facing. It will also shed light on how the site of Bat is perceived by the local community and visitors.
Design/methodology/approach
The archaeological complex of Bat, al-Khutm, and al-Ayn was listed by the UNESCO as a world heritage site in 1988. Despite this classification, relatively little attention has been given to the management of this site. The author conducted interviews with representatives of the MHC in order to understand how this site is being managed, and the author uploaded an online public questionnaire to learn how the population is being educated about the importance of this heritage.
Findings
The results of this investigation revealed a surprisingly high level of public awareness about the importance of this site to the country socially, and economically. In spite of this awareness, the site is not visited frequently because it is not adequately equipped: a situation that was clearly outlined by the respondents. Suggestions were proposed in order to better integrate this site into the local development plans and the socio-economic growth of the whole region.
Originality/value
The originality of this research is that it took the site of investigation an archaeological site listed by the UNESCO for its outstanding universal value and contrary to what is expected, this site was “forgotten” in all development and management plans executed by the local and central government for almost two decades. It is also the first research about a site in Oman to address such issues and use these methods.